JDBC ResultSet scrollable result set

Scrollable result set

1)Com.microsoft.sqlserver.jdbc.SQLServerException: The requested operation is not supported for a forward-only result set.

When TYPE is set to:resultset.type_forward_only (default), the cursor cannot be moved arbitrarily, but only step forward, otherwise it will be reported sqlserverexception

Example:

statement = con.preparestatement (sql, resultset.type_forward_only, resultset.concur_xxx); rs = Statement.executequery (); Rs.absolute (2); System.out.println (rs.getstring ("Virusid") + "" +rs.getstring ("Featurecode") + "" +rs.getstring ("apppackage") + "" + Rs.getint ("Virustype") + "");

2) Com.microsoft.sqlserver.jdbc.SQLServerException: The result set does not go forward.

When TYPE is set to:resultset.type_scroll_insensitive or resultset.type_scroll_insensitive, the cursor can be moved, but the position moved is [1,count], Remember not to start from 0, or you will get an error.

Now that you can move, explain a few ways to move:

rs = Statement.executequery (); The cursor points to the position in front of the first line, where the data cannot be retrieved or an error occurs: The result set does not go forward

Rs.next (); The cursor moves down one position and returns true if there is a result set in place, otherwise false

Rs.previous (); The cursor moves up one position and returns true if there is a result set in place, otherwise false

Rs.first (); Where the cursor points to the first row

Rs.last (); Where the cursor points to the last row

Rs.beforefirst (); The cursor points to the position in front of the first row, where the data cannot be obtained

Rs.afterlast (); The cursor points to the position following the last line, which cannot fetch data

Rs.absolute (index); Cursor moves to index position, index is any number of [1,count], but cannot exceed, otherwise error

Rs.relative (index); The cursor moves the index position from the current position, that is, relative movement, index can be negative, but the result is also within [1,count]

Isafterlast (); Determines whether the cursor is after the last row.

Isbeforefirst ();//Determines whether the cursor precedes the first row.

Iffirst (); Determines whether the cursor points to the first row of the result set.

Islast (); Determines whether the cursor points to the last row of the result set.

GetRow ();//Gets the line number of the row to which the current cursor is pointing, starting with line number 1, or 0 if the result set has no rows.

Example:

statement = con.preparestatement (sql, resultset.type_scroll_insensitive, resultset.concur_xxx); rs = Statement.executequery (); Rs.absolute (1); System.out.println (rs.getstring ("Virusid") + "" +rs.getstring ("Featurecode") + "" +rs.getstring ("apppackage") + "" + Rs.getint ("Virustype") + "");

3)differences between resultset.type_scroll_insensitive and Resultset.type_scroll_insensitive

Many people say that the former is insensitive to data changes in the database and the latter is sensitive. But when I used the SQLServer2005 test, I really did not see the difference between the two, if someone saw can be posted code to learn from each other .....

In addition, the development process is seldom used, I think type_scroll_insensitive is enough.

Attention:

Pre-run Script:

IF not EXISTS (SELECT * from sysobjects WHERE id = object_id (' tbl_virusbaseinfo ') and type = ' U ') BEGIN CREATE TABLE Tbl_vi Rusbaseinfo (uidvirusid varchar) NOT NULL, Strfeaturecode varchar (null,strapppackage varchar) NULL, Ivirustype int null, CONSTRAINT pk_virusbaseinfo PRIMARY KEY (uidvirusid)) END Go

  public static connection  Getconnection () {connection con = null;try {string username =  "sa";  //   Username string password =  "123"; //  Password Class.forName (" Com.microsoft.sqlserver.jdbc.SQLServerDriver ");//  load the driver class Con = drivermanager.getconnection (" JDBC: Sqlserver://127.0.0.1:1433;databasename=testdb ", Username, password);//  Get the connection} catch  ( classnotfoundexception e)  {e.printstacktrace ();}  catch  (sqlexception e)  {e.printstacktrace ();} Return con;}  

@Testpublic void Resultsettest () {Connection con = getconnection (); String sql = "Select Uidvirusid,strfeaturecode,strapppackage,ivirustype from Tbl_virusbaseinfo"; PreparedStatement statement = null; ResultSet rs = null;try {statement = con.preparestatement (sql, resultset.type_scroll_sensitive, Resultset.concur_read_ only); rs = Statement.executequery (); Rs.absolute (3); System.out.println (rs.getstring ("Uidvirusid") + "" +rs.getstring ("Strfeaturecode")); catch (SQLException e) {e.printstacktrace ();} Finally{try {if (rs! = null) {Rs.close ();} if (statement! = NULL) {Statement.close ();} if (con! = null) {Con.close ();}} catch (SQLException e) {e.printstacktrace ();}}

Finally: Leave a question about how sensitivity and insensitivity are differentiated.

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JDBC ResultSet scrollable result set